ADR-161 implemented RunMode::Single (AtomicBool re-entrancy guard) + Parallel
but honestly left Restart/Queued/max as "ACCEPTED-FUTURE / unbounded parallel" —
every non-Single mode spawned an unbounded task. This makes them real.
New `runmode` module — per-automation RunState owns the machinery:
- Restart: aborts the in-flight action task (tokio::task::AbortHandle) and
starts a fresh one.
- Queued: serializes runs in arrival order via a per-automation async Mutex —
sequential, never concurrent, nothing dropped.
- max: N: caps concurrency at N via a per-automation Semaphore; triggers beyond
N queue (await a permit) rather than running concurrently (HA bounded
semantics). Documented in the module table.
- Single/IgnoreFirst/Parallel preserved.
engine.rs now holds a RunState per registration and calls run_state.dispatch()
at all three trigger sites (event loop, timer, fire_time_for_test); the old
spawn_run is removed. engine.rs trimmed to 433 lines.
Tests (tests/engine_behaviors.rs) — verified to FAIL on the old unbounded-
parallel dispatch (simulated and confirmed each panics), pass on the new:
- restart_mode_cancels_prior_run (old: both runs complete → 2; new: 1)
- queued_mode_runs_sequentially_not_concurrently (old: max concurrency 3; new:
all 3 run, max concurrency 1)
- max_two_caps_concurrency_at_two (old: 4 concurrent; new: all 4 run, max 2)
homecore-automation --no-default-features: 45 passed (lib 37, engine_behaviors
8), 0 failed.
Co-Authored-By: claude-flow <ruv@ruv.net>
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